Flagrant foul
 

We had a JV girls game, defender pushes in the back forcefully the player that is shooting a driving layup. Player misses the shot and crashes face down to the floor, the ref covering the play rushes in and says very audibly "flagrant foul" while raising his index finger into the air (seemed even louder bcuz gym was sparsely populated). He told us at halftime that it was the signal for a "flagrant foul". He was the senior crew member somewhere 20+ years it is widely known.
Is that proper sign or has he been influenced by watching too much tv?

You Are Outta Here ...
 

No (see signal chart) and yes (especially baseball).

Note: Video is R rated. Make sure the little tikes are out of the room.

<iframe width="560" height="315" src="https://www.youtube.com/embed/f6cmqUTPn08" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>

There is no signal. Did everyone know what he meant? Then good for him. (and yes, I recognize there are exceptions and times when "only" the proper signal should be used).

Reminds me of the time when some signal was added -- the rationale was "everyone uses this signal and it adds an explanation so we should adopt it" at the same time the emphasis was "only approved signals." If you are using only approved signals , you'll never get a new, good, signal added.

Bob, that is one great observation! (Among many others over the years)